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701.
Scarpino Schietroma DM Monaco MR Bucalossi V Walter PE Gentili P Bella M 《Organic & biomolecular chemistry》2012,10(24):4692-4695
A catalytic version of the Rabe electrophilic amination is presented. This kind of reaction was originally employed in 1918 in a key step for the conversion of quinotoxine to quinine. Ketones and α-substituted aldehydes give the corresponding α-aminated carbonyl compounds in moderate yield. α,α-Unsubstituted aldehydes give rise to amino ketones via a novel rearrangement. 相似文献
702.
Capriotti AL Caruso G Cavaliere C Foglia P Laganà A Samperi R 《Natural product research》2012,26(19):1787-1795
Polyphenol concentrations were quantified by rapid resolution liquid chromatography/mass spectrometry in white table grape. The experimental vineyard was subjected to different kinds of water supply and supply rates. Samples from the same vineyards were also analysed after 6 weeks of storage in a refrigerator and after 6 weeks of delayed harvesting. Berry skins and seeds were analysed separately. A statistical treatment of the screening kind, namely the 2(k) full factorial design, was used for the interpretation of results. Storage, delayed harvesting and the different kinds of water supply appeared to be the variables most affecting grape polyphenol content. In some cases, results showed that polyphenol content diminished by more than 50% after 6 weeks if the grapes were stored in a refrigerator, or if a sprinkler was used for irrigation. 相似文献
703.
Electrostatic assembly of Ag nanoparticles onto nanofibrillated cellulose for antibacterial paper products 总被引:1,自引:0,他引:1
Natércia C. T. Martins Carmen S. R. Freire Ricardo J. B. Pinto Susana C. M. Fernandes Carlos Pascoal Neto Armando J. D. Silvestre Jessica Causio Giovanni Baldi Patrizia Sadocco Tito Trindade 《Cellulose (London, England)》2012,19(4):1425-1436
Nanofibrillated cellulose offers new technological solutions for the development of paper products. Here, composites of nanofibrillated cellulose (NFC) and Ag nanoparticles (NP) were prepared for the first time via the electrostatic assembly of Ag NP (aqueous colloids) onto NFC. Distinct polyelectrolytes have been investigated as macromolecular linkers in order to evaluate their effects on the building-up of Ag modified NFC and also on the final properties of the NFC/Ag composite materials. The NFC/Ag nanocomposites were first investigated for their antibacterial properties towards S. aureus and K. pneumoniae microorganisms as compared to NFC modified by polyelectrolytes linkers without Ag. Subsequently, the antibacterial NFC/Ag nanocomposites were used as fillers in starch based coating formulations for Eucalyptus globulus-based paper sheets. The potential of this approach to produce antimicrobial paper products will be discussed on the basis of complementary optical, air barrier and mechanical data. 相似文献
704.
Giovanni Visco Susanne Heidi Plattner Patrizia Fortini Maria Pia Sammartino 《Chemistry Central journal》2012,6(1):1-17
Background
This paper discusses results obtained in the second monitoring campaign of the Carcer Tullianum, a particular hypogeum environment located in the historical centre of Rome (Italy). In the first paper we stressed the need to apply chemometric tools to this kind of studies in order to obtain full and significant information; really information on sampling design, sensors (type, number, position) and instrument validation seems to be not easy to find in literature for researches dealing with monitoring of indoor environments. Also in this case three main parameters (temperature, humidity, illuminance) were monitored in the complex construction by an inexpensive self-assembled system along some horizontal and vertical vectors together with some measurements of oxygen, carbon dioxide and barometric pressure. With respect to the first campaign, we used a higher number of sensors to cover a new excavated zone; for the same reason, as well as to take into account the presence of visitors, a different experimental design was adopted.Results
Different data treatments were applied to data coming from all the used sensors. A good view of the microclimate was obtained that also resulted coherent with the different position of the three rooms constituting the monitored site (Carcer, Tullianum, Convent). Classical time plots resulted useful to evidence the correlation of the main monitored parameters (T, RH% and illuminance) with macroclimate, as well as their delay in following macroclimate. Box-Whisker and Gain-Loss graphs evidenced at the best the microclimate differences between the three rooms; an almost hypogean microclimate was evidenced for the lower room (Tullianum) where humidity values range between 90 and 100% while lower values, but anyway higher than the external, and spread more widely were measured passing to Convent and Carcer with minimum values around 50% for the last. A scarce or very scarce correlation with macroclimate was evidenced for all the three main measured parameters. Lighting results mainly dependent on artificial light and only in few cases, but unfortunately in the most precious zone, illuminance exceeds values suggested by Normative.Conclusions
Box-Whisker and Gain-Loss graphs allowed us to have the best view of the microclimate for all the monitored rooms. The influence of lighting by lamps on the other monitored parameters resulted overlapped and clearly topped the solar one. The worst situation was found in the Carcer, where the presence of the main chandelier worsens the state of the frescoed walls, already subjected to wide changes in temperature and humidity. Also the lighthouse located above the Convent provokes lighting exceeding values suggested by Normative while, as expected, LEDs resulted as suitable source of light from a conservation point of view. Susanne Heidi Plattner, Patrizia Fortini and Maria Pia Sammartino contributed equally to this work 相似文献705.
David Cruz-Uribe Patrizia Di Gironimo Luigi D’Onofrio 《Czechoslovak Mathematical Journal》2012,62(1):111-116
In this paper we establish a continuity result for local minimizers of some quasilinear functionals that satisfy degenerate
elliptic bounds. The non-negative function which measures the degree of degeneracy is assumed to be exponentially integrable.
The minimizers are shown to have a modulus of continuity controlled by log log(1/|x|)−1. Our proof adapts ideas developed for solutions of degenerate elliptic equations by J. Onninen, X. Zhong: Continuity of solutions of linear, degenerate elliptic equations, Ann. Sc. Norm. Super. Pisa Cl. Sci. (5) 6 (2007), 103–116. 相似文献
706.
Geudtner G Janetzko F Köster AM Vela A Calaminici P 《Journal of computational chemistry》2006,27(4):483-490
The parallelization of the LCGTO-KS-DFT code deMon2k is presented. The parallelization of the three-center electron repulsion integrals, the numerical integration using a direct grid algorithm and the matrix multiplication and diagonalization are described. The efficiency of the parallelization is analyzed by selected benchmark calculations. It is shown that geometry optimizations of systems with more than 8,000 basis functions are feasible on cluster architectures. 相似文献
707.
King-Díaz B Macías-Ruvalcaba NA Aguilar-Martínez M Calaminici P Köster AM Gómez-Sandoval Z Reveles JU Lotina-Hennsen B 《Journal of photochemistry and photobiology. B, Biology》2006,83(2):105-113
Nineteen 2-[(R-phenyl)amine]-1,4-naphthalendione derivatives (PAN) were tested on spinach thylakoids for their activity as electron acceptors. These molecules act as photosystem I electron acceptors in the micromolar range. AC(50) values varied from 5 nM to 24 microM. QSAR analysis revealed a linear correlation of the m-PAN derivative log [1/AC(50)] with the energy difference of the LUMO and HOMO orbitals. The biological activity of p-PAN derivatives correlates linearly with structural parameters. Electron affinity is being the most important. The half wave I potential values (E(1/2)) of PAN compounds (from -213 to -569 mV vs. NHE) match with the mid-point potentials of the A(0) to F(X) niche of PSI electron transport carriers. The logP values of PAN derivatives were 3.35 and 3.88, indicating that they are hydrophobic compounds. Therefore PAN compounds accept electrons at the hydrophobic A(0) to F(X) niche of PSI. 相似文献
708.
Luciano Callipo Patrizia Foglia Riccardo Gubbiotti Roberto Samperi Aldo Laganà 《Analytical and bioanalytical chemistry》2009,394(3):811-820
A method for carbonic anhydrase II (CA II) absolute quantification in human serum is presented. This method is based on high-performance
liquid chromatography (HPLC)-Chip microfluidic device incorporating a nanoelectrospray source interfaced to a triple quadrupole
mass spectrometer. The fraction containing CA II was isolated by preparative reversed-phase HPLC, and peptides obtained from
the tryptic digest of the protein mixture were separated by the HPLC-Chip system. The multiple-reaction monitoring acquisition
mode of a selected suitable CA II peptide and peptide internal standard allowed the selective and sensitive determination
of a CA II. Absolute recovery of the method was 52 ± 12%, while analytical recovery was 81 ± 10%. For the eight samples analyzed,
the matrix effect was found to be only −14 ± 6%. A comparison among three regression lines type which were obtained by external
calibration, matrix-matched calibration, and standard addition method, respectively, demonstrated that the first one is adequate
in obtaining good accuracy and precision. Method quantification limit for CA II in serum was estimated to be 2 fmol/mL. CA
II mean concentration in sera from eight healthy subjects was found to be 56 pmol/mL (relative standard deviation 24%). 相似文献
709.
Patrizia Beraldi Maria Elena Bruni Antonio Violi 《Computational Optimization and Applications》2012,51(3):1375-1396
Capital rationing is a major problem in managerial decision making. The classical mathematical formulation of the problem
relies on a multi-dimensional knapsack model with known input parameters. Since capital rationing is carried out in conditions
where uncertainty is the rule rather than the exception, the hypothesis of deterministic data limits the applicability of
deterministic formulations in real settings. This paper proposes a stochastic version of the capital rationing problem which
explicitly accounts for uncertainty. In particular, a mathematical formulation is provided in the framework of stochastic
programming with joint probabilistic constraints and a novel solution approach is proposed. The basic model is also extended
to include specific risk measures. Preliminary computational results are presented and discussed. 相似文献
710.
Prof. Francesco Sannicolò Prof. Patrizia R. Mussini Prof. Tiziana Benincori Prof. Rocco Martinazzo Dr. Serena Arnaboldi Giulio Appoloni Dr. Monica Panigati Dr. Elsa Quartapelle Procopio Valentina Marino Dr. Roberto Cirilli Dr. Simone Casolo Prof. Wlodzimierz Kutner Dr. Krzysztof Noworyta Dr. Agnieszka Pietrzyk‐Le Zofia Iskierko Katarzyna Bartold 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10681-10681